Support for heat-treating containers



Sept. 11, 1945. H. H. HARRIS SUPPORT. FOR HEAT TREATING CONTAINERS FiledFeb. 27. 1943 INVENTOR HenrH H. Harris ATTORNEYS Patented Sept. 11, 1945TE-DSTATES PATENT oFFicE CON Harris, Champalgn, 1!]. ApplicationFebruary 27, 1943, Serial N0. 477,475

2 Claims.

My invention relates generally to work containing receptacles, and inparticular to work containing receptacles adapted to be" moved through aheat treating furnace. My invention will be described in respect to awork support used in the carburizing process, but itsuse need notnecessarily be so limited, the device being equally usable in otherprocesses.

When conventional containers are used in heat treating furnaces, thework to be treated is'placed inside the boxes and embedded in acarbonaceous material such as bone dust and the like. The boxes are thencovered over with heavy trays, and inverted, with the trays on theunderside, and in this position placed on skid rails or tracks withinthe furnace. The trays are arranged within the furnace in end-to-end orside-by-side abutting relationship and thrust applied to the rearmosttray is transmitted down to the line from tray to tray to the endmos'ttray. In this manner, the loaded trays are passed through the cycle instepby-step movementuntil pushed out at the discharge end of thefurnace.

The trays support the work being treated as well as the weight of thecarbonaceous material; the

trays serve as closures for the boxes and support the boxes within whichthe work is contained, andthey also serve to transmit the moving thrustfrom one tiny to'the next, down the line. In use, the trays aresubjected to the rough handling incident to the process, .as well as toextremely high furnace temperatures and sudden changes'in temperatures,and all too often the trays develop cracks, shrinksand warpages and haveto be replaced at relatively frequent intervals. Conventionally, boththe trays and boxes have been made of thick section material, at someexpense and with appreciable weight, and their too frequentfailure -inuse involves considerable cost. The weight of the boxes and trays isalso a factor in the power needed to move them through the furnace.

The general objective of this invention is the simplification of theapparatus used in supporting the work being treated, while retaining allthe functions of the devices conventionally in use.

The main object of my invention is the provision of a work container,means to close same and means to support same during movement through afurnace. In my device, I have done away with the heavy tray-closure usedas a support, and close the container with one element and support thecontainer on other elements.

Another object of my invention is the provision of a work container andsupport means therefor keyed thereunto for movement through a furnace.

Still another object of my invention ls'the provision of awork'contain'er and support means therefor keyed thereunto, the supportsreceiving and transmitting the thrust of travelling move ment throughthefur'nace. v r

Further objects of my invention will apear during the course of thefollowing description of several ilustrative embodiments thereof.

In the drawing annexed hereto, and forming a part hereof,

, Figure l is a plan View, partly in section and partly broken away, ofone form of deviceconstructed according toand embodying my, invention; Ia I Fig. 2' is a longitudinal section along the line 2-4 of Fig. 1- alsoartly broken away; and

Fig. 3 is a transverse section on the line 3-4 of Fig.l.-

My device, indicated generally by reference numeral l0, comprises a pairof track or rail overlying shoes or skids 12, HI,- of substantiallyequal length. Shoes 12, Hi are cast or otherwise formed of high heat andcorrosion resisting alloy maupstanding side walls Hi, 20. The outer'wafl18 on each shoe extends upwardly and inwardly over plate I6, short ofthe center thereof, and the inner wall 20 of each shoe also extendsupwardly and inwardly over the plate, short of the center thereof. Thespacing betweenthe wall-ends de fines'a channel 22 extendingsubstantially the full length of each shoe. As seen in Fig. 3, the innerwalls Mare shorter than the outer walls It. A number of laterally spacedapart blocks 24, 24 are formed on top of walls 29 along the edges ofchannels 22, the purpose of which will be given below.

One of the shoes, as l2, may have a pair of integrally formed legs 26,26 depending from the sides thereof, defining a channel 28. Legs 26, ateach end of the shoe are flared outwardly, as at 30, to serve to guidethe shoes onto the skid rails or tracks, legs 26, 26 straddling one ofthe tracks or rails within the furnace to keep the shoes alignedthereon.

I provide a plate 40, which may be of generally rectangular shape, butwith rounded corners. Plate 40 need not be particularly thick, but maybe slightly bowed and provided with a few strengthening transversecorrugations 42. Plate 40 need be strong enough to support only theweight of the charge being heat treated and the formed of high heat andcorrosion-resisting alloy,

""form size, so as to be interchangeable with parts material, and is ofgenerally conventional rec-" tangular shape, the sides of which are nothicker] than the width of channel 22. Box 60 is prefer."'

ably formed of greater length and width than plate 40, and preferably ofsuch width as to overlie a pair of rails or tracks within the furnace. Acatch 62 i formed on the outside of each of the end walls of the box.

- "In use, boxBfl is inverted, openend upwards,

and charged with the work to be treated and with thecarbonaceous'material. Theplate 40 is then'fitted withinlthe open end ofthe box and loops or-bai1s 50-swung down and over catches 62, Shoes I2,l4 may then'be inverted and fitted over and onto'the sides ofbox'60, orthe ,box may be inverted andset into the shoes. Whichever sequence ofsteps is followed, the entire combination is then disposed atop a pairof parallel tracks or rails within the furnace.

As seen in Fig. 1, the ends of shoes l2 and I 4 extend beyond walls [8,20. Inner wall is shorterthan outer wall I8, and at the ends thereof-,-the walls curve inwardly of the shoeto a point where the upstandingportion of the wall merges into the floor portion of the shoe, as at 10.The outer; walls l8 curve correspondingly, keeping the width of channel22 constant. The curvature of the channel serves, therefore,to locateshoes l2, l2 on box 60, and insure proper alignment of the shoes. Avertically upstanding, apertured lug or ear member 12 is formed at-eachend of the shoes, preferably integral with the shoes, and I may providemy box 60 with a pair of horizontally extending arms 14, 14 at each endthereof, to line upwith the lugs 12. A pin passed through registeringapertures in thearms and lugs will serve to further lock the box ontothe shoes.

After'the loaded box is inverted, spot welds may be formed as at 64, 66,to further lock plate 40 to'box 60. The weight of the charge will causeplate or web 40 to bear down on shoes [2, l4 and the alignment of bails50, 50 on catches 62 willcenter the plate against blocks 24, -24.

' A number of loaded containers, mounted on shoes such as thosehereinabove may then be disposed within the furnace in end-to-endrelationship, the shoes of one butting against'the lighter andthinnersection material than heretofore. I

The device of. my invention, as a unit, is easily assembled for use, andjust as easily dismantled.

.Plates, boxes, shoes, etc., may be formed of uni- 'of other units. Theshoes may be formed of extra heavy material, since they must absorb andtransmit the moving thrust.

' The box is, in and of itself, a rigid beam member, capable ofmaintaining its shape if supported at any two or more points. A heavytray, as in conventional practice, is not at all necessary to. supportthe box, and in my invention, the thrust tubes or shoes I2 and I4support the box, the plate and the work thereon. The thrust tubes andbox may be formedof uniform section, and the use of these thrust tubeslocalizing'all compression strains results in much longer alloy life. Aweight saving of up to 45% is secured with my device, which isoperationally more ellicient, than the conventional arrangements.

Having now described my invention, what I claim and desiretosecure byLetters Patent is:

l. Incombination, for use in a heattreating furnace having railstherewithin, ani-inverted open-mouthed work container,- a closuretherefor fitting into the container, cooperating means on-the closure.and on the container to maintain the closurewithin the containenand aplurality of containerand closure-supporting rail-overlying means, saidrail-overlying means being longitudinally channeled to receive thecontainer therewithin and support same thereon, said railoverlyingmeansalso having a platform portio thereon to support the closure.

2. In combination, for use in a heattreating furnace having railstherewithin, an inverted open-mouthed work container, a closure thereforfitting into the container, cooperating means on the closure and on thecontainer to maintain'the closure within the container, andrail-overlying means comprising a plurality of elongated thrust beams tosupport the container and the closure, each. beam having a pair of wallsextending upwardly thereof to define a longitudinally extending channeltherebetween to .receive the container therewithin and support samethereon, one of the walls of each thrust beam beingbent over inwardlythereof to form a platform portion to support the closure thereon.

HENRY animals.

